user10704: I only have a passing knowledge of Buddhism. I keep coming across people (buddhaghoSha, shAntideva, nAgArjuna, vasubandhu, asanga, etc.) who wrote authoritative works on Buddhism. And yet, I don't see it mentioned that they themselves attained Buddhahood. 
Hence my question: who were some people who definitely attained Buddhahood after the historical Buddha, Gautama? Or would I be correct in my suspicion that no one did (but many came "very close"), and the next Buddha would be Maitreya?
Many thanks in advance!

user-1: Your presumption is more or less correct if we are talking about a Samyaksambuddha.  That's a Buddha who is completely enlightened without karmic remainder, a knower of worlds, an incomprapable tamer of persons to be tamed, and so on and so forth as the the suttas put it.  There is only one of those per world system per age.  Shakyamuni Buddha was the last and Maitreya will supposedly be the next.
There have been, however, plenty of people (and I'd include those you've listed) who have reached full enlightenment (e.g. arahat status or nth stage Bodhisattvas...depending on your flavor of Buddhism).  In fact, enlightenment itself isn't even all that rare.  Those who find it, however, just aren't endowed with the other attributes that are accumulated over an almost incalculable amount of meritorious lives and make a full Buddha an unsurpassed, well-gone, teacher of gods and men.

user4888: Buddhahood isn't the only source of authority in Buddhism. We have four stages of enlightenment, the final stage is an Arahant. 
An arahant is like a Buddha in that both understand the nature of the mind and they no longer experience suffering of any kind. Because an arahant can experience dharma first-hand they are an authoritative source for Buddhism. Arahants aren't that uncommon or hard to find but we can't prove that someone is an arahant so we just get different lineages who claim that their teacher is an arahant and they treat their teacher as a source of authority. For example see Ajahn Jayasaro's book on page 6 where he claims that Ajahn chah (the teacher he trained under) was an aharant.
There are a few differences between an arahant and a Buddha. A Buddha is a type of arahant who has discovered the dharma by themselves without the guidence of another arahant. Since they discovered it themselves they have a superior ability in teaching the dharma.
I'm uncertain if the authors you mention are claimed to be arahants or even if they are at a lesser stage of enlightenment but we do have many sources of authority which appeared after the historical Buddha's death.

10704: <p>I only have a passing knowledge of Buddhism. I keep coming across people (buddhaghoSha, shAntideva, nAgArjuna, vasubandhu, asanga, etc.) who wrote authoritative works on Buddhism. And yet, I don't see it mentioned that they themselves attained Buddhahood. </p>

<p>Hence my question: who were some people who definitely attained Buddhahood after the historical Buddha, Gautama? Or would I be correct in my suspicion that no one did (but many came "very close"), and the next Buddha would be Maitreya?</p>

<p>Many thanks in advance!</p>
 -1: <p>Your presumption is more or less correct if we are talking about a Samyaksambuddha.  That's a Buddha who is completely enlightened without karmic remainder, a knower of worlds, an incomprapable tamer of persons to be tamed, and so on and so forth as the the suttas put it.  There is only one of those per world system per age.  Shakyamuni Buddha was the last and Maitreya will supposedly be the next.</p>

<p>There have been, however, plenty of people (and I'd include those you've listed) who have reached full enlightenment (e.g. arahat status or nth stage Bodhisattvas...depending on your flavor of Buddhism).  In fact, enlightenment itself isn't even all that rare.  Those who find it, however, just aren't endowed with the other attributes that are accumulated over an almost incalculable amount of meritorious lives and make a full Buddha an unsurpassed, well-gone, teacher of gods and men.</p>
 4888: <p>Buddhahood isn't the only source of authority in Buddhism. We have <a href="https://en.wikipedia.org/wiki/Four_stages_of_enlightenment" rel="nofollow noreferrer">four stages of enlightenment</a>, the final stage is an Arahant. </p>

<p>An arahant is like a Buddha in that both understand the nature of the mind and they no longer experience suffering of any kind. Because an arahant can experience dharma first-hand they are an authoritative source for Buddhism. Arahants aren't <em>that</em> uncommon or hard to find but we can't prove that someone is an arahant so we just get different lineages who claim that their teacher is an arahant and they treat their teacher as a source of authority. For example see <a href="https://tisarana.ca/static/books/jayasaro_the_real_practice.pdf" rel="nofollow noreferrer">Ajahn Jayasaro's book</a> on page 6 where he claims that Ajahn chah (the teacher he trained under) was an aharant.</p>

<p>There are a few differences between an arahant and a Buddha. A Buddha is a type of arahant who has discovered the dharma by themselves without the guidence of another arahant. Since they discovered it themselves they have a superior ability in teaching the dharma.</p>

<p>I'm uncertain if the authors you mention are claimed to be arahants or even if they are at a lesser stage of enlightenment but we do have many sources of authority which appeared after the historical Buddha's death.</p>
