Following the Dhamma without taking refuge

Householder Konrad, interested,

Going for refuge, seeking refuge under the Tripple Gems - without such any long lasting success:

No, not really, only Paccecabuddhas would be able to practice the Noble-Path without refuge. Just think on how many livetimes the Bodhisatta hardly tried, and how good he tried in relation to western/modern people today, who think such might be possible, easier. At times the Dhamma of the Buddha is still vitally alive by the Sangha of the Buddhas good following monk, even such a person, having such potency or having reached the path, as well as those who had won the path in previous existance, would seek out for the refuge under the Tripple Gems, eventually join the Sangha also outwardly.

Some issues on that matter on faulty refuge or no have been answered here: How does one become a lay Buddhist?.

Today there are many how think "love and marriage" can be seperated, seeking after avoiding certain duties that come from relationship and also hold on greedy on old habits, views and relations, but all those popular approaches, often hardly neglecting monasticism and renounced life, would, how much what ever thought practiced, not equal only taking refuge into the Buddha, his good Dhamma and his straight following disciples on the road of homelessness.

So again in short to the two questions:

Can a person follow the Buddha's teachings without taking refuge?

Generally no. Only a very seldom Paccecabuddha-canditate could, and he would not having get known our current Buddha, Dhamma, Sangha.

Can someone attain enlightment without taking refuge?

Again: Generally no. Only a very seldom Paccecabuddha-canditate could, and he would not having get known our current Buddha, Dhamma, Sangha.

So good to hurry, seek out and nourish inwardly and outwardly the Tripple Gems and ones relation tendency because not even difficult to trace this days but also fast disappearing for the most. No more tracing is already a sign for one to possible have lost the track of Upanissaya (strong condition), which relays on paccaya (causes given) from ones past and present actions by thoughts, words and deeds.

Hurry up if feeling, seeing, seriousness would bring great long term happiness and beyond.

(Note that this gift of Dhamma is not dedicated for trade, exchange, stacks or entertainment but as a means to make merits toward release from this wheel)

Refuge is the only way of practicing Buddhism. Yes, you can learn about Buddhism before taking Refuge, but if you are serious about Buddhism you cannot progress along the path without taking Refuge. Why? Because nowhere in Buddhism can you practice without a teacher. Even Buddha's still acknowledge the connection to their own teachers (e.g. Chenrezi and Amitabha). Without a teacher or guru, your ego will be your principle guide - as we see with the extraction of core Buddhist teachings like yoga or mindfulness - those practices taken outside of the Buddhist construct are simply serving a worldly agenda - yoga for the sake of good health and vitality alone contradicts the idea that Samsara is suffering and we need to abandon self-cherishing (not that taking care of yourself is bad, but it boils down to your motivation, therefore anyone could practice yoga but to what end?) Similarly, mindfulness was only ever meant to be practiced in order to observe our mind and keep it on a moral track and also, in the broader context, of assimilating the view of emptiness into our view by observing the nature of mind. Mindfulness taken outside of this framework only serves the purpose to which it is applied, which (without a teacher or guru guiding us) is likely going to be ego. We see this in all the self-improvement workshops that take elements of mindfulness and other meditation practices but place them in a secular context to make them more universally acceptable - for instance, being mindful in the workplace. Essentially, that agenda is only serving whatever the employer's agenda is. Which is probably not Buddhism (e.g. selflessness / abandonment of self-clinging). In fact, we often see mindfulness meditation being used in the context of "self" improvement, which is the total opposite of Buddhist ideology as the "self" is the root of all suffering. In short, why would you want to practice Buddhism without taking Refuge? Either you are a theist and believe in a God - therefore Buddhism is not for you anyway - or you are an atheist but don't acknowledge that self-cherishing is the root of suffering and so want to practice elements of Buddhism to bolster your self-identity. Or, you are simply too proud to follow a teacher - in which case any real blessings of practice will never enter your heart. You can learn about Buddhism without taking Refuge but you cannot be a Buddhist without taking Refuge. Ergo, you can practice calm-abiding, but only in the context of testing the water to see if Buddhism is for you or not. To extract an element of Buddhist practice with no intention of ever taking Refuge is not Buddhism. It's something else. We see this in the hugely popular workshops of people like Kabat-Zinn - who studied Buddhism but maintained his Judaeo-Christian beliefs and stripped any reference to Buddhism in his mindfulness workshops.
The teachings are very powerful and attractive to people, but it all boils down to motivation. At the heart of Buddhism is loving-kindness for others and the abandonment of self-cherishing. When you take Refuge, that is the core of what you are taking Refuge in - "From this day forth, I take Refuge in the Buddha, Dharma and Sangha in order to achieve Enlightenment for the benefit of all beings". So, by default we can assume that anyone who doesn't want to take Refuge but still wants to engage in Buddhist practices is only doing so for their own benefit alone. Without a guide, we are lost in an ocean of suffering.

The answer is a definite yes according to the Pali Suttas (Buddhavacana).

Bhagavaa Buddho (Bhagavaa) is the Buddha in the Suttas. The truths he pointed out to the world is the Dhamma of Bhagavaa. These truths apply to all beings, including humans. No label is required to shape one's life according to these truths. His fundamental advice was to refrain from all evil. (sabba paapassa akaranam) The evil here is what is considered as evil by the society one lives in. This was advice given to the Kaalaamas in the Kaalaama sutta.

Buddhism, Buddhist etc. are labels which have no meaning in Buddhavacana.

In his book "Le bouddhisme: une philosophie du bonheur?" (Buddhism: a philosophy of happiness?), Philippe Cornu says this about the refuge ceremony (my translation):

There are as many Buddhist rites as there are schools [...] Among all, taking Refuge or the act of going for the Triple Refuge is the most fundamental of Buddhist rites, which serves as the link between all the traditions. To go for Refuge is the profession of one's faith and the founding act by which one marks his entry in the Buddhist path. One thus places his faith in three objects of refuge: the Buddha as a perfectly enlightened being and the principle of Enlightenment; the Dharma, the teaching and its application by way of practice; and the Sangha or the virtuous community, in this case the âryasangha, the community of those who have obtained Enlightenment and not the entirety of the faitfhful. [...] "to turn towards" Refuge as the model to follow, is an internal decision, the fruit of a conviction that the Buddhadharma is the appropriate spiritual path to follow, that one chooses to follow, and the realization that Enlightenment is potentially attainable in the short or long term. Nothing in this "conversion" of the mind is externally visible [...]

Contrary to baptism or the Judaic rites of circumscision that take place shortly after birth, the Refuge stems thus from a strictly personal commitment, and the act of taking Refuge, which consists of repeating the spell of the Triple Refuge with a firm, confident and clear intention, must be renewed regularly, at least once a day, [...] individually this time, without ceremony or ritual. Why repeat incessantly the precept of Refuge? Because of the impermanance and because of the fact that our mind is quick to forget its spiritual commitments.

As far as I can remember, at least in the Pāli canon, there was nothing explicitly prohibiting people from following the teachings without taking Refuge. On the other hand, I don't believe that this encourages a "one foot in the water one foot on the ground" attitude. It's rather that the act of taking Refuge was considered a matter of fact decision for those deciding to follow the Buddha, because the canon is packed to the brim with examples of people taking Refuge after a discussion with the Buddha- both monks and lay followers. Benefiting from something and actively pursuing that thing are 2 different matters. There are for example Christians who've integrated Zen meditation into their practice, and they see absolutely no problem with it (and rightfully so) because they're just benefiting from a certain Buddhist teaching, they're not commiting to Buddhism.
It seems to me then that a person cannot "follow" the Buddha's teaching without taking Refuge (as far as people that that do have the possibility to go for Refuge are concerned of course). However one can still definitely benefit from it in various ways.

Attaining Enlightenment without taking Refuge is possible. According to Buddhism, innumerable Buddhas and arahants appeared in ages where there were no Buddhist teachings, and can still appear (paccekabuddhas). But just because this is possible doesn't mean that it's an easy matter since reaching Enlightenment is already a very difficult task for Buddhists. People who are very spritually advanced can do it without following Buddhism, normal people (pretty much all of us) cannot.

The guiding principles concerning Refuge is thus, as I understand it, intention and commitment. Taking Refuge is just a technique to help a practitioner retain his commitment to the teachings, nothing more. It has no value in and off of itself. If a person is serious about following the Buddha, Refuge will naturally follow if there are no obstacles to it.

As for abandoning one's old religion due to making an "official" entry into the Buddhist path, that's pretty much what has to happen. A person cannot be, for example, Muslim and Christian at the same time. It's the same with Buddhism because its "endgame" is irreconciliably different from the one that Abrahamic religions have.
On the other hand this doesn't mean that former Christians have to abandon and "betray" Jesus or the entirety of Christian teachings. A number of teachings point to the same things as in Buddhism and those practitioners will benefit from them. Jesus' life, even with his holy nature taken out of the picture, can be an interesting study for Buddhists. The Buddha did not harbour enmity against other religions and if I remember correctly advised his newly "converted" disciples to not sever friendly relationships with their old teachers. From this we can see that while severing links with the teachings of one's former religion is necessary, there's no incitement whatsoever towards taking a negative attitude against them.
Within this light, taking Refuge and entering the path must be a well-reflected upon decision, if one is hesitating about doing it due to considerations about the former religion then one shouldn't do it until that hesitation is dealt with.

Can you follow the Buddha's teachings (Kamma laws, meditation, metta, etc.) without taking refuge?

Absolutely! Whatever elements of Sat-Dharma you can incorporate in your life are going to be beneficial. It does not have to be "all or nothing". However, the extent to which you follow Sat-Dharma is the extent to which you benefit.

Can someone attain enlightenment without taking refuge?

The world does not care about official ceremonies! :) What matters is your determination. To attain enlightenment, in your heart you have to be fully committed to the spiritual quest. That's the true meaning of taking refuge.

Does taking refuge in the Triple Treasure mean your old religion should be abandoned?

Regardless of your cultural background, the spiritual quest has one goal: completion. Taking refuge implies unwavering commitment to that, above worldly quests and goals. The tri-ratna is a further development of this idea, with Buddha taken as an inspiration of someone who successfully made it, Dharma taken as a guidebook, and Sangha as companions. However, despite an instrumental role of tradition, the only real working basis is one's own fundamental sanity.

What is the main benefit of taking refuge?

It is like when you lived with a girlfriend for 5 years, and finally you two decided to make it official. If love and commitment were NOT there to begin with, the wedding ceremony can't improve anything, and if love and commitment were there all the time, the ceremony does not change anything. However, in your relationships with external world, you can now firmly say "I am a married man, and she is my wife" -- which makes things simpler and gives you a sort of strength.