That is questioning what someone thinks. Racism is the holding of racial prejudice. The person who knows if any act was committed due to racial prejudice is the person who commits the act. 1/2 https://twitter.com/jmkorhon_en/status/1280402168382709761

We don't have to think every individual has 100% self-awareness of their own motivations to accept that they know them better than someone else who is motivated to read them through any ideological lens. 2/3

This is important for three main reasons.
1) The individual genuinely is the one with access to their own mind so most likely to be right about what is going on in there.
2) Recognising individual agency to hold or reject certain ideas is essential to any aim for moral progress.

3) The right of all people to the privacy of their own minds & conscience. You simply do not know or have the right to know what is going on in there & you cannot force confessions of sins you believe other people must have because of your own worldview. This is secularism.