Many skeptics have restricted their skepticism to a particular domain of supposed knowledge:

1. External world

2. Other minds

3. Past and future

4. Unperceived objects

Skepticism is the attitude of doubting everything and questing the genuineness of any particular subject. There are mainly two forms of skepticism. One is when a person thinks that he knowns nothing. And the other is which states that no person is capable enough of justifying things.

Skeptics have restricted their skepticism in all four domains. Examples of these domains are knowledge of external world, knowledge of other minds, knowledge of past and future, and knowledge of unperceived objects.

This type of skepticism is quite common and is known as the limited skepticism. There are numerous difference in opinions regarding this in various writings.