Skeptics argue that due to the limitations of our senses and the fallibility of our reasoning, we can never be certain of the truth of our beliefs.

The skeptical regress argues that any attempt to justify a belief leads to an infinite chain of justifications, with no ultimate foundation.

Skeptics often use arguments like this to challenge the certainty of our beliefs, particularly those that are based on faith or tradition.

While skepticism raises doubts about the certainty of our knowledge, it does not necessarily lead to a complete rejection of all beliefs. Most skeptics argue that we can still make reasonable decisions and live fulfilling lives, even in the absence of absolute certainty.

Pragmatism is a philosophical approach that emphasizes the practical consequences of beliefs rather than their truth or certainty. Pragmatists argue that we should judge beliefs based on their usefulness and effectiveness in helping us navigate the world.

Pyrrhonian skeptics argue that we should suspend judgment on all beliefs, while Academic skeptics believe that we can still hold beliefs, but we should be aware of their uncertain nature.

The Liar paradox is a famous skeptical argument that challenges the possibility of truth and certainty. It states that if someone says 'I am lying,' and they are telling the truth, then they are lying. But if they are lying, then they are telling the truth. This paradox leads to a contradiction and raises doubts about the reliability of language and our ability to make true statements.

One of the main criticisms of skepticism is that it is self-refuting. If skepticism is true, then we cannot know anything, including the truth of skepticism itself. This leads to a contradiction and undermines the skeptic's own position.

The brain in a vat argument is a skeptical argument that challenges the existence of the external world. It proposes the scenario of a brain that has been removed from its body and placed in a vat of nutrients, with electrodes connected to it that stimulate it to experience a simulated reality. The argument suggests that we cannot know for certain whether we are brains in vats or if the external world is real.

Skepticism challenges the idea that we can have certain knowledge of reality. Skeptics argue that our senses and our reasoning are unreliable, and that we can never be sure that our beliefs about reality are true. This leads to the conclusion that reality is ultimately unknowable.

The argument from illusion is a skeptical argument that challenges the reliability of our senses by pointing out that our senses can be deceived. For example, we may see a mirage in the desert or hear a voice that is not there. This argument suggests that we cannot trust our senses to give us accurate information about the world.

Skepticism challenges the idea that there are objective moral truths that apply to everyone. Skeptics argue that our moral beliefs are based on our personal experiences, our culture, and our upbringing, and that there is no way to determine which moral beliefs are true and which are false. This leads to the conclusion that moral beliefs are subjective and that there is no such thing as moral objectivity.

The argument from evil is a skeptical argument that challenges the existence of God by pointing out the problem of evil in the world. If God is all-powerful, all-knowing, and all-loving, then why does evil exist? Skeptics argue that the existence of evil is incompatible with the existence of a benevolent and omnipotent God.

Skepticism challenges the idea that we can have certain and infallible knowledge. Skeptics argue that our knowledge is always provisional and subject to revision. This is because our knowledge is based on our senses, our reasoning, and our beliefs, all of which are fallible. As a result, we can never be sure that our knowledge is true.

The argument from regress is a skeptical argument that challenges the possibility of certainty by pointing out that any attempt to justify a belief leads to an infinite chain of justifications. For example, if we try to justify our belief that the sun will rise tomorrow, we might appeal to the fact that it has always risen in the past. But then we need to justify our belief that the sun will continue to rise in the future, and so on. This leads to an infinite chain of justifications, with no ultimate foundation.