To find the sentence that disrupts the paragraph's logical flow, we'll analyze each sentence's content and connection to the others:
1. Sentence Analysis:
- Sentence 1: "Animals have an interest in fulfilling their basic needs, but also in avoiding suffering, and thus we ought to extend moral consideration."
- Sentence 2: "Singer viewed himself as a utilitarian, and presents a direct moral theory concerning animal rights, in contrast to indirect positions, such as welfarist views."
- Sentence 3: "He argued for extending moral consideration to animals because, similar to humans, animals have certain significant interests."
- Sentence 4: "The event that publicly announced animal rights as a legitimate issue within contemporary philosophy was Peter Singer’s Animal Liberation text in 1975."
- Sentence 5: "As such, we ought to view their interests alongside and equal to human interests, which results in humans having direct moral duties towards animals."
2. Logical Sequence:
Sentences 1, 3, and 5 all address the concept of moral consideration for animals, focusing on their interests and our corresponding duties. Sentence 2 provides context for Peter Singer's utilitarian approach to animal rights, which supports this ethical argument. Sentence 4, however, solely discusses the historical impact of Singer's book, "Animal Liberation," as a landmark publication.
3. Conclusion:
Sentence 4 is centered on historical significance rather than developing the core argument about animal rights and moral duties. Therefore, Sentence 4 is the sentence that doesn't fit with the paragraph's primary focus on ethical arguments for animal rights.