将模型的布尔值设置为字符串会使其为false

Question

我有一个Answer，其response属性是一个布尔值。如果我将answer.response设置为'abcde'，则响应设置为false。

class Answer < ActiveRecord::Base
  belongs_to :answer_sheet
  belongs_to :question

  validates :response, inclusion: [true, false]
end

class AnswersController < ApplicationController
  def create
    answer = Answer.find_or_initialize_by(
      answer_sheet_id: answer_params[:answer_sheet_id],
      question_id: answer_params[:question_id]
    )
    answer.response = answer_params[:response]
    answer.save

    render json: answer, status: :created
  end
end

知道为什么会这样吗？我很沮丧。我原以为验证失败了。