The Redpill is a rejection and opposition to the bluepill. It is a negative stance on a popular, pleasant falsehood. With regards to mainstream mores, it represents the counter-culture opposed to the prevailing social norm. The blackpill is the redpill with an emphasis on things that are out of control.
The origin of the phrase “redpill”, “bluepill” and it’s variants is from the “Red Pill Or Blue Pill” scene from The Matrix, where the protagonist, Neo, is forced to decide whether to take the red pill or the blue pill. The red pill would let him discover the truth about the world, and the blue pill would send him back to the Matrix not knowing anything. Neo takes the red pill and the movie proceeds. 
To pick-up artists, and many online dating coaches, etc, the "red pill" means to acknowledge that self-improving confidence through self-talk or achievements (i.e. "game") is the primary factor in attracting women.
Colloquially and politically, the redpill refers to masculinist and/or alt-right opinions that one could find in anti-leftist online circles. Not all redpillers are incels and not all incels are redpillers. The first major self-identified redpill community was started by a Republican congressman, but political undertones are less emphasized in the incelosphere compared to the blackpill.
Many redpillers often see the Purplepill as the political antitheses of those on the incelosphere. With their ideologies having being extremely in conflict with each other, such as Redpillers often aligning themselves with right-wing, MRA and MGTOW ideology. While Purplepillers often are leaning towards Leftism, inter-sectional anti-sexism, post-feminist and post MRA ideology. To this day these two philosophies are still in conflict with each other, however due to the noticeable decline in red pill ideology, the purple pill has often been seen as it's successor on the incelosphere.
When sticking to its original etymology, the redpill is never a positive belief in and of itself, but rather is defined by a reaction to a precursory stance, i.e. the bluepill (see Neo's trajectory). For conventional proponents of the redpill, their stance on any specific redpilled issue becomes obsolete as soon as the precursory bluepill stance ceases being imperative within society. Similar to the question of whether a 5 ft 8 inch man is tall would fluctuate depending on whether he's in the Netherlands or Indonesia, whether one is redpilled similarly oscillates depending on the bluepill.
Due to the mainstream media's tendency to tag anyone who doesn't fall in line with feminist thought processes as an "extremist", or "figure of hate", there is an increasing tendency among redpillers (or anti-bluepillers) to avoid the usage of any uncountable noun or agent noun (such as redpiller) to describe themselves. Instead, in an effort to thwart the mainstream media's misrepresentation of their views, the use adjectives wherein the focus is to shift attention from themselves, to the opponent, through adjectives such as anti-bluepill.
Many "Leftists" (often liberal radfems in practice) from sites such as Twitter & Tumblr will often steryotype all incels as redpillers, with Purplepill advocates often getting associated with the redpill and being dog-pilled, whether or not said advocates are actually willing to debate their ideals.
- (MRA sense) The belief that society is gynocentric and discriminates against men rather than women. As well as valuing male gender traits over female gender traits.
- (PUA sense) Use of game to attract women. Use of musclemaxxing, masturbation restriction, social dominance, 'frame', and other popular 1990s-type dating advice for men to attract women. A proactive instead of fatalist mindset.
- (Political sense) Self-identified reactionary/right-winger/social-conservative, i.e. "Kanye supports Trump now? He's taken the Redpill man"
- Note: Believing in the MRA or PUA sense of the redpill does not imply belief in the political sense of the redpill necessarily. Although use of the political sense of the word usually implies belief in either the MRA or PUA sense. Also, the term 'redpill' is never used to refer to left-wing politics in any context. That would be the Purplepill.
- Looks are most important thing for men to attract women in 2020.
- Not having your own place, your own car or your own money isn't that much of a detriment as you think.
- Face is the most important aspect of looks on men.
- Bodybuilding won't make you slay if you have an average face, or if you currently don't have much success with women.
- Females rate up to 80% of men as below average looking.
- Females say how personality and confidence matters, but it only pertains to long-term relationships. Even then, it's not as important as looks.
- Females lie about their past sexual experiences.
- Females make it easy for males who they want for a short-term relationship. They make it hard for males who they want for a long-term relationship. For example, for a STR, they will have sex on the first "date". But for a LTR, they will make him wait.
- A short-term relationship is a code word for a hypergamous relationship in which the male is higher in league than the female.
- Females have many options, especially pertaining to casual sex.
- Most females are already having sex. Even most single females are having casual sex.
- Average men are judged negatively due to the halo effect.
- Even the most "non-primitive" appearing females are slutty.
- Homosexuals, bisexuals and pansexuals are either an evolutionary strategy, and/or an enemy to men.
- Starting to fucking believe the Blackpill. Ex told the piece of shit she cheated on me with that he was better than me. I found texts between my now ex and the garbage human being she cheated with. Apparently, she told him he was better than me during sex and even in normal conversation. This guy is a disrespectful ass, has a minimum wage job, NO car, and no education. I have a degree (about to have two), a nice car, a good job for my age and I’ve treated her very well. Yet THAT is better than me. Just because he’s taller and better-looking, she genuinely thought he was better than me. I’m fucking reeling.
- He was 35 years old and lived with his mother where he made money by selling drugs. This poor poor guy just couldn't get a real job you see. Because he already had three kids from three different women and if he got a regular job they could get child support from him.
- Pill jargon
- Rollo Tomassi
- Redpill Bible
- New Age Movement