| A standard is neither immutable nor absolute. (PS 7) |
| The conceptual model of choice process. (PS 59) |
| A sign that does not affect behavior has no meaning. (PS 170) |
| We can observe the properties of a social group without observing the properties of its members. (PS 211) |
| The artificial reality model. (PS 235) |
| Without ideals man's life is purposeless. (PS 241) |
| Decline and doom are not inevitable; nor is survival. (RF 3) |
| The effectiveness of experience as a teacher has decreased. (RF 5) |