Step 1: Understanding Spinoza’s Philosophy.
Baruch Spinoza, a 17th-century philosopher, is known for his work on ethics and pantheism. He believed that the intellectual love of God is the highest form of love, where the mind, through reason, comes to understand and love the divine. For Spinoza, God and nature were one, and true understanding leads to a rational and intellectual connection with the divine.
Step 2: Analyzing the Options.
- 1. Spinoza: This is correct. Spinoza emphasized the intellectual love of God as a key element of his ethical philosophy.
- 2. Descartes: Descartes focused on skepticism and the mind-body dualism but did not propose the intellectual love of God.
- 3. Kant: Kant focused on moral philosophy and the categorical imperative, rather than the concept of intellectual love of God.
- 4. Karl Marx: Marx was an atheist and did not deal with the concept of intellectual love of God; he critiqued religion from a materialist perspective.
Step 3: Conclusion.
The correct answer is 1. Spinoza.
Final Answer:
\[
\boxed{\text{The correct answer is 1. Spinoza.}}
\]