Adler’s classic sayings are as follows:

1. A person who is not interested in others will encounter the most difficulties in his life and do the most harm to others. All human failures stem from such people.

2. The courage to deal with various problems in life can explain how a person defines the meaning of life.

3. When we know that suicide must be a kind of blame or revenge, we can understand that suicide is actually a personal struggle for superiority.

4. Dedication is the true meaning of life. If we looked today at the relics we inherited from our ancestors, what would we see? What they left behind is their contribution to human life.

5. Dedication is the true meaning of life.

6. It is always easier to defend one's beliefs than to comply with them.

7. Life is about constantly comparing yourself with your "ideal self", rather than living under the evaluation of others.