Syllogism — Premises: (a) All dogs are books. (b) All books are pictures. Conclusions: I) All dogs are pictures. II) All books are dogs. III) All pictures are dogs. IV) Some pictures are books.

Introduction / Context:
Two nested universals are provided. We assess which of the four conclusions are compelled by these inclusions.

Given Data / Assumptions:

• Dogs ⊆ Books.
• Books ⊆ Pictures.
• Ordinary-language assumption: the class 'Books' is non-empty, so existential statements about some members are acceptable in exam settings.

Concept / Approach:
Transitivity of subset gives Dogs ⊆ Pictures (I). The converses (II, III) are not supported. From Books ⊆ Pictures and non-emptiness, there exists at least one entity that is both picture and book, validating IV.

Step-by-Step Solution:

Verification / Alternative check:
Take one concrete book; it is also a picture, satisfying IV. Dogs being a subset of books ensures I.

Why Other Options Are Wrong:
Options that include II or III assume unsupported converses or overgeneralization.

Common Pitfalls:
Confusing subset direction and presuming equivalences where only one-way inclusion exists.

Final Answer:
Only I and IV follow.